. >> repororter: anday johnson says tonight, dhs and the fbi are closely monitoringvents in paris. but he says we know of no specific or creditable threats on the united states tonight. of course, there were no threats on paris either. these are the kinds of attacks not only hard to detect, but very hard to stop. >> indeed. resignation resignation, people sayinge can't protect ourselves. and 73% of americans saying, it's likely there will be a terrorist attack coming in the future that will cause the loss of lives. when you hear people in new york city talking about this, resigned, how do we stop it? we can't change the way we live, right? >> you can't changnge the way we live. but looking at the attacks since 9/11, they're negligible. nothing close to what we saw in paris. >> and we thought there was a big number of attackers, because of the scope of it. it's actually shrunk down. >> you can see the amount of mayhem done by a small amount of people. and the mumbai attack, just ten attackers attackers, over 400 people killed or wounded. this looks like five or six killing 200 peopl